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1.
Summary The levels of rat plasma -macroglobulins, -cysteine proteinase inhibitor, haptoglobin and antipapain activity were studied during the acute-phase reaction after an injection of -pinen. An increase in concentration of all the compounds examined was observed.  相似文献   

2.
Summary Ascorbic acid and glutathione concentrations increase in brown fat of cold-exposed rats. This phenomenon can be reproduced by noradrenaline or isoproterenol administration, and thus seems to be under sympathetic control. Histological study shows ascorbic acid storage in brown adipocyte nuclei.  相似文献   

3.
Summary A sensitive radioimmunoassay showed that circulating -interferon in the plasma of healthy individuals was low in children and reached the highest level in the young adult, then declined gradually with age. Circulating -interferon was 0.201±0.059 ng/ml in males (n=19) and 0.184±0.076 ng/ml in females (n=14) at ages 30–39 years old. It was noted that circulating -interferon was maintained up to a certain level even in elderly individuals.  相似文献   

4.
Summary Enzymatic hydrolysis of several racemic N-phenylacetyl--methyl--amino acids containing an additinal aliphatic, aromatic or polar substitutent on the chiral carbon atom, has been studied by using benzylpenicillincylase fromEscherichia coli A.T.C.C. 9637. Both the rate of hydrolysis and the stereoselectivity were found to be considerably lower than in the case of natural -amino acids. Steric and electronic factors in the side chains influencing the stereoselectivity are discussed.  相似文献   

5.
Summary Axillary 5-androst-16-en-3-one (5-androstenone) levels were found to be significantly higher in men than in women but do not vary between left and right axillae, are not related to age, handedness or degree of hirsutism (in women) nor to anosmia to this steroid. In men (but not in women), levels are related linearly to axillary cholesterol concentrations but not to squalene. Olfactory thresholds for 5-androstenone varied widely, the lowest recorded being 0.2 ppb, but there was no difference in thresholds between men and women. Women (70%) found the smell repellant but anosmia did not differ greatly between men and women (9–20%). Anosmia to the smell of 5-androst-16-en-3-ol was most marked in women (90%) rather than in men (45%). Axillary 5-androstenone values were generally consistent with the musky or strong smells of male axillary extracts, compared with the sweet smell of those from female subjects.Supported by the Herbert Dunhill Trust.  相似文献   

6.
Summary -MSH (0.1, 1, 10 g) was administered intracerebroventricularly and its action on pain sensitivity was investigated by the hot-plate method in mice. -MSH produced dose-dependent analgesia and this analgesic effect was prevented by naloxone (1 mg/kg, s.c.). It is possible that -MSH may play a role in the mechanism of pain through endogeneous opioid systems.  相似文献   

7.
Information on the bioactivities of non-mammalian cytokines is scant due to the lack of the recombinant molecules and specific antibodies. We produced the mature predicted peptide of tumor necrosis factor (TNF) from the bony fish gilthead seabream (Sparus aurata L.) (sbTNF), and its biological role was determined in vitro and in vivo. We first demonstrated by analytical size-exclusion chromatography that sbTNF is an oligomeric protein but the dimer appears to predominate over the trimeric form, in contrast to mammalian TNF. Intraperitoneal injection of native sbTNF resulted in (i) priming of the respiratory burst of the peritoneal exudate and head-kidney (HK) leukocytes, the latter being the bone marrow equivalent in fish; (ii) rapid recruitment of phagocytic granulocytes to the injection site, and (iii) induction of granulopoiesis in the HK. Interestingly, sbTNF was able to induce a strong proliferation of HK cells in vitro, whereas human TNF did not. Conversely, sbTNF was not cytotoxic for murine L929 fibroblasts.Received 12 February 2004; received after revision 15 March 2004; accepted 29 March 2004  相似文献   

8.
In crustaceans, all the steps in the assimilation of food take place in the hepatopancreas. To facilitate the study of this organ, a method for the dissociation of cell types was developed. The hepatopancreas of the prawnPalaemon serratus was mechanically dissociated and the cells separated by Percoll density-gradient centrifugation. The E and R cells had similar densities of around 1.05 g/ml. The F cells were separated into two distinct fractions with densities of 1.075 and 1.082 g/ml. The B cells sedimented at a density of 1.12 g/ml. The ratio between the two populations of F cells was found to vary during the intermolt cycle while B cells disappeared after the molt. When the density gradient fractions were incubated with3H-leucine, incorporation was highest in the F cell fractions. Measurements of -amylase activity, indicated that the two populations of F cells may be derived from the same cell type.  相似文献   

9.
We have reviewed the methodology for an accurate quantitation of Hb F in the blood of patients with sickle cell anemia, values observed in hundreds of patients of different (racial or ethnic) backgrounds and with differences in severity of the disease, and the various factors that affect the level of Hb F. The latter include sex, age, genetic background or chromosomal haplotypes, variations in the sequences of the locus control region(s) 5 to the -globin gene, and the presence of an chain deficiency or -thalassemia. Finally, a few remarks about agents effective in increasing the in vivo Hb F synthesis are also included.  相似文献   

10.
Differences in the tissue content of prothymosin during the early postnatal development of male and female rats are reported. Thymus and spleen have been found to contain significantly higher amounts of prothymosin in the newborn and prepubertal animals, as compared to adults, whereas liver has been found to contain low levels of prothymosin throughout development. These findings indicate a functional association of prothymosin with the proliferating lymphoid tissues of the young rat.  相似文献   

11.
The field of Parkinsons disease pathogenesis is rapidly evolving from the one of a monolithic and obscure entity into the one of a complex scenario with several known molecular players. The ongoing systematic exploration of the genome holds great promise for the identification of the genetic factors conferring susceptibility to the common non-Mendelian forms of this disease. However, most of the progress of the last 5 years has come from the successful mapping and cloning of genes responsible for rare Mendelian variants of Parkinsons disease. These discoveries are providing tremendous help in understanding the molecular mechanisms of this devastating disease. Here we review the genetics of the monogenic forms of Parkinsons disease. Moreover, we focus on the mechanisms of disease caused by -synuclein and parkin mutations, and the implications of this growing body of knowledge for understanding the pathogenesis of the common forms of the disease. Received 10 March 2004; received after revision 26 April 2004; accepted 29 April 2004  相似文献   

12.
Summary In the normal Wistar rat, the plasma -MSH level was raised by hypertonic saline injection (as compared with control rats injected with isotonic saline). No such rise in -MSH followed hypertonic saline administration in the Brattleboro (hereditary diabetes insipidus) animal (compared to isotonic saline injected controls). It is suggested that, in the rat, endogenous antidiuretic hormone is involved in the secretory response of the pars intermedia to osmotic stimuli.  相似文献   

13.
Summary In the rabbit isolated aorta, hymenin (10–6 M) a novel marine alkaloid, caused a parallel rightward shift of the dose-response curve for norepinephrine without affecting that for histamine or KCl, suggesting that hymenin is a competitive antagonist of -adrenoceptors in vascular smooth muscles.Acknowledgments. We thank Ms A. Kajiwara and Ms M. Hamashima of this institute for their technical assistance, and Prof. Y. Hirata of Meijo University for his encouragement.  相似文献   

14.
Summary Ethanol may modulate endogenous opioid systems by disrupting opioid receptor signalling. Low concentrations of ethanol slightly potentiate -opioid receptor binding by increasing receptor Bmax, and, in some cases, chronic ethanol exposure decreases the density or affinity of the -opioid receptors. By contrast, high concentrations of ethanol acutely decrease -opioid receptor binding by decreasing receptor affinity, whereas chronic exposure of animals and neuronal cell lines to lower concentrations of ethanol leads to possibly adaptive increases in the density or affinity of the -opioid receptors. In the neuronal cell line NG108-15, ethanol does not up-regulate the -opioid receptor by blocking receptor degradation or endocytosis, but protein synthesis is required for this response. Up-regulation of the -opioid receptor renders ethanol-treated NG108-15 cells 3.5-fold more sensitive to opioid inhibition of adenylyl cyclase. Long-term treatment with ethanol also increases maximal opioid inhibition in NG108-15 cells, possibly by decreasing levels of Gs and its mRNA. Ethanol differentially modulates signal transduction proteins in three additional neuronal cell lines, N18TG2, N4TG1, and N1E-115. Ethanol-treated N18TG2 cells show the least up-regulation of the -opioid receptor, little heterologous desensitization of adenylyl cyclase, and no changes in Gs or Gi. By contrast, ethanol-treated N1E-115 cells show the largest up-regulation of the -opioid receptor, the most heterologous desensitization of adenylyl cyclase, and concentration-dependent decreases in Gs and increases in Gi. Further analysis of these related neuronal cell lines may help to identify the molecular elements that endow some, but not all, neuronal cells with the capacity to adapt to ethanol.  相似文献   

15.
The goal of this article is twofold: 1) It aims at providing an overview on some major results obtained from energy flow studies in individuals, populations, and communities, and 2) it will also focus on major mechanisms explaining community structures. The basis for any biological community to survive and establish a certain population density is on the one hand energy fixation by primary producers together with adequate nutrient supply and the transfer of energy between trophic levels (bottom-up effect). On the other hand, predator pressures may strongly control prey population densities one or more trophic levels below (top-down effect). Other interpopulation effects include competition, chemical interactions and evolutionary genetic processes, which further interact and result in the specific structuring of any community with respect to species composition and population sizes.  相似文献   

16.
17.
Summary Human 2-macroglobulin-human pancreatic elastase II binding were investigated using a homologous substrate, human aortic elastin, in order to test the enzymatic activity. We demonstrated that two moles of 2-M are required to inhibit one mole of HPEII when the enzyme is added to a mixture of elastin and 2-M. In addition, when the elastase-2-M complex is prepared under some circumstances, it exhibits an elastinolytic activity.  相似文献   

18.
19.
Summary Adenomatous prolactin cells lose 39% of their cytoplasm volume within 7 days after the beginning of bromocriptine treatment. A simultaneous reduction of the rough-surfaced endoplasmic reticulum and the Golgi apparatus occurs. Their membranes are removed by rapid transport along the secretory pathway to the cell surface and to lysosomal destruction.We thank Prof. E. del Pozo, Sandoz Ltd, Basle, for the generous gift of injectable bromocriptine, Prof. E.R. Weibel, Dept. of Anatomy, University of Bern, for his technical advice, Dr U. Helfenstein, Institute of Biostatistics, University of Zürich, for his help in the statistical evaluation of the results and the EMDO-Foundation, Zürich, for financial support.  相似文献   

20.
Summary We describe here a further Japanese family with pyrimidine 5-nucleotidase (P5N) deficiency diagnosed using a nuclear magnetic resonance (NMR) spectrum, in Kumamoto prefecture where two families having the disease have been reported before. The specific spectra in1H-NMR of P5N deficient erythrocytes were due to three methyl protons of CDP-choline at 3.22 ppm and to H-2, H-8 and ribose-1 of pyrimidine nucleotide phosphate(s) in the lower fields (at 5.82 and 8.00 ppm). The other specificities in31P-NMR spectra were due to CDP-choline, CDP-ethanolamine and UDP-glucose. Those spectra were not detected in other types of hemolytic anemia.  相似文献   

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